1. Field of the Invention
The present invention relates to a capacitive touch panel, and more particularly, to a seamless capacitive touch panel.
2. Description of the Prior Art
In recent years, mobile phones with touch panels have become more and more popular in the market. Therefore, more developers are developing various types of touch panels. Among those touch panels, capacitive touch panels have better endurance and feel, and have become the next generation of touch panels instead of resistive touch panels. However, the capacitive touch panel has higher cost, which is the main reason the capacitive touch panels have not enjoyed wider implementation in consumer products.
Please refer to FIG. 1, which is a diagram showing electrodes of a projected capacitive touch device of the prior art. The projected capacitive touch device senses a touched position by the two layers of the electrodes. The projected capacitive touch device comprises a substrate (not shown), such as a glass substrate. A cover layer (not shown) is arranged on the glass substrate. A Y-axis electrode layer 12 is arranged on an upper surface of the glass substrate. The Y-axis electrode layer 12 comprises a plurality of Y-axis electrodes y1, y2, y3, y4 separated from each other by a fixed distance. An X-axis electrode layer 11 is arranged on a lower surface of the glass substrate. The X-axis electrode layer 11 comprises a plurality of X-axis electrodes x1, x2, x3, x4 separated from each other by a fixed distance. The Y-axis electrodes y1, y2, y3, y4 are orthogonal to the X-axis electrodes x1, x2, x3, x4. When a finger touches or is close to the cover layer, a capacitance value between the X-axis electrode and the Y-axis electrode at the touched position changes. After sensing the change of the capacitance value by a sensing circuit, an X-axis coordinate and a Y-axis coordinate of the touched position can be determined. The above capacitive touch device needs the X-axis electrodes and the Y-axis electrodes to be arranged on the lower surface and the upper surface of the glass substrate respectively, or on a same surface of the glass substrate with an isolating layer to separate the X-axis electrodes from the Y-axis electrodes.
Please refer to FIG. 2, FIG. 2 is a cross-sectional view of a capacitive touch panel of the prior art. The capacitive touch panel comprises a transparent substrate 21 and a transparent cover plate 25. A lower transparent conductive layer 22, an isolating layer 23, and an upper transparent conductive layer 24 are sequentially formed on the transparent substrate 21. The transparent cover plate is bonded to the transparent substrate 21 by optical clear adhesive 26 to form the capacitive touch panel. As shown in FIG. 1, the capacitive touch panel comprises the X-axis electrodes and the Y-axis electrodes. The X-axis electrodes are formed at the lower transparent conductive layer 22, and the Y-axis electrodes are formed at the upper transparent conductive layer 24. However, the X-axis electrodes and the Y-axis electrodes are formed at different transparent conductive layers. When the X-axis electrodes and the Y-axis electrodes are not aligned properly, a thin line can be seen at a seam between the X-axis electrode and the Y-axis electrode, which affects image quality of a touch screen.